I am thinking about pouring a slab of concrete in my back yard so I have something level and solid to set up on. My question is, when you extend the legs of your Atlas, how far apart are the feet from one another? Can I talk some one into taking their Atlas out and a tape measure and checking?

I don't know exactly the size of your mount's footprint, but I poured a concrete slab in my backyard for a larger mount and made it 7' X 7'. This size is large enough but my thinking was to make it larger than necessary in the event that I later went to a larger mount.

Fully extended, the feet of my Atlas EQ-G end up 54" apart.
Hope that helps!

Thanks!
I was going to build like a compact "observabox" sort of like the one: observabox

Though it would be more of a roll-away and probably not built as good. I was going to use a 48"x48"x4" thick slab just something to keep the mount from digging into the soil and level. Looks like I may need to go a little bigger. Probably should wait until I have the mount in my hands before I start diging a hole and mixing concrete eh?